Temperature, air pollution, and hospitalization for cardiovascular diseases among elderly people in Denver.

Abstract

Daily measures of maximum temperature, particulate matter less than or equal to 10 micro m in aerodynamic diameter (PM10), and gaseous pollution (ozone, nitrogen dioxide, sulfur dioxide, and carbon monoxide) were collected in Denver, Colorado, in July and August between 1993 and 1997. We then compared these exposures with concurrent data on the number of daily hospital admissions for cardiovascular diseases in men and women > 65 years of age. Generalized linear models, assuming a Poisson error structure for the selected cardiovascular disease hospital admissions, were constructed to evaluate the associations with air pollution and temperature. After adjusting the admission data for yearly trends, day-of-week effects, ambient maximum temperature, and dew point temperature, we studied the associations of the pollutants in single-pollutant models with lag times of 0-4 days. The results suggest that O3 is associated with an increase in the risk of hospitalization for acute myocardial infarction, coronary atherosclerosis, and pulmonary heart disease. SO2 appears to be related to increased hospital stays for cardiac dysrhythmias, and CO is significantly associated with congestive heart failure. No association was found between particulate matter or NO2 and any of the health outcomes. Males tend to have higher numbers of hospital admissions than do females for all of the selected cardiovascular diseases, except for congestive heart failure. Higher temperatures appear to be an important factor in increasing the frequency of hospitalization for acute myocardial infarction and congestive heart failure, and are associated with a decrease in the frequency of visits for coronary atherosclerosis and pulmonary heart disease.

The toxicology of climate change: Environmental contaminants in a warming world

“…Qian et al (2008) found a synergistic effect of PM 10 and high temperatures on daily cardio-respiratory (Bell et al, 2007;Confalonieri et al, 2007;Dominici et al, 2006;Fiala et al, 2003;IPCC, 2007a;Katsouyanni et al, 1993;Knowlton et al, 2004;Koken et al, 2003;Mauzerall et al, 2005;Ordonez et al, 2005;Rainham and Smoyer-Tomic, 2003;Ren and Tong, 2006) ▪ The elderly and individuals with pre-existing cardio-respiratory disease may be more vulnerable to these effects Altered exposure and risk ▪ Some populations may experience increases or decreases in POP exposures and health risks depending on the region and diet of exposed individuals (Bard, 1999;Gordon, 1997;McKone et al, 1996;Watkinson et al, 2003) ▪ Pesticides may impair mechanisms of temperature regulation especially during times of thermal stress Increased susceptibility to pathogens ▪ Toxicants can suppress immune function, and climate-induced shifts in disease vector range will result in novel pathogen exposure (Abadin et al, 2007;Haines et al, 2006;Lipp et al, 2002;Nagayama et al, 2007;Patz et al, 2005;Rogers and Randolph, 2000;Smialowicz et al, 2001) ▪ Immune system impairment linked to toxicants may increase human vulnerability to climate shifts in pathogens ▪ Low-income populations, infants, children, and the chronically ill may be more susceptible exposures may sensitize individuals to allergic disease ▪ Low-income populations, infants, children, and the chronically ill may be more susceptible mortality in Wuhan, China. The PM 10 effects were strongest on extremely high temperature days (daily average temperature 33.1°C) and weakest during normal temperature days (daily average temperature 18°C).…”

“…However, a number of studies suggest that the toxicity of ozone and PM will be exacerbated with global warming, and some of these data support that older adults will be especially vulnerable (Bell et al, 2007;Confalonieri et al, 2007;Dominici et al, 2006;Fiala et al, 2003;IPCC, 2007c;Katsouyanni et al, 1993;Knowlton et al, 2004;Koken et al, 2003;Mauzerall et al, 2005;Ordonez et al, 2005;Rainham and Smoyer-Tomic, 2003;Ren and Tong, 2006). Other potential interactions between climate change and toxicant exposure include increased susceptibility to pathogens (Abadin et al, 2007;Nagayama et al, 2007;Smialowicz et al, 2001) and aeroallergens (D'Amato et al, 2002;Diaz-Sanchez et al, 2003;Epstein, 2005;Janssen et al, 2003).…”

“…Ebi et al (2006) note that there will be 100 million more Americans that are aged 65 or older in 2100 than in 2000, leading to generally increased vulnerability of the U.S. population to climate sensitive health outcomes. The effects of contaminants on vulnerable subpopulations warrant further study, although there is evidence that older individuals will be more susceptible to climate-air pollutant interactions (Fiala et al, 2003;Koken et al, 2003;Ordonez et al, 2005). In addition, low-income populations, infants, children, and chronically ill individuals may be especially susceptible to climate sensitive outcomes linked to interactions between pollutant exposures and changes in vector-borne and allergic disease (D'Amato et al, 2002;Diaz-Sanchez et al, 2003;Epstein, 2005;Haines et al, 2006;Janssen et al, 2003).…”

“…Epidemiological evidence suggests that heat exacerbates mortality and morbidity from cardio-respiratory disease in humans exposed to ozone and PM (Fiala et al, 2003;IPCC, 2007c;Koken et al, 2003;Ordonez et al, 2005;Rainham and Smoyer-Tomic, 2003). During the European heat wave of 2003, there was a surge in respiratory illnesses that was associated with increased concentrations of particulates and ozone especially among the elderly (Fiala et al, 2003;Ordonez et al, 2005).…”

“…During the European heat wave of 2003, there was a surge in respiratory illnesses that was associated with increased concentrations of particulates and ozone especially among the elderly (Fiala et al, 2003;Ordonez et al, 2005). In another study illustrating the effects of climate sensitive outcomes on vulnerable older populations, males in Denver, Colorado aged 65 and older were found to be at increased risk for hospitalization for acute myocardial infarction, coronary arteriosclerosis, and pulmonary heart disease when co-exposed to higher temperatures and ozone (Koken et al, 2003). More recently, Bell et al (2008) examined confounding factors, including air pollution levels, on heat-related mortality in three Latin American cities: Mexico City, Mexico, Sao Paulo, Brazil, and Santiago, Chile.…”